Changeover valve



June 9, 1953 N. H. SIEBENS 2,641,273

CHANGEOVER VALVE Filed Oct. 18, 1947 ZSheets-Sheet 1 INVENTOR. '53 NORMAN/4% S/EBEMs ATTORNEY Patented June 9, 1953 CHANGEOVER VALVE Norman Harry Siebens, Cedar Grove, N. J., as-

signor to C-O-Two Fire Equipment Company, Newark, N. J a corporation of Delaware Application October 18, 1947, Serial No. 780,715

Claims.

The present invention relates to fluid systems and more particularly to a changeover valve by which one or the other of two sources of fluid may be successively connected to a discharge line.

The changeover valve is of particular use in carbonating devices in which water from a reservoir or other large supply is carbonated from a comparatively small source of carbon dioxide stored under high pressure in a container.

Heretofore, it has been the practice in some cases to provide such systems with two containers of carbon dioxide which are connected to the carbonator, one of the containers having its valve opened while the other container is kept in reserve with its valve closed. When the first container has been discharged so that the pressure of the remaining carbon dioxide is too low for eiiective carbonation, the reserve container is put into service by opening its valve and closing the valve of the emptied container.

It is difficult to determine the amount of carbon dioxide remaining in a container while carbon dioxide liquid is present. Gauges are unsatisfactory for this purpose as the carbon dioxide liquid will maintain the vapor pressure of the carbon dioxide gas at practically a constant value, irrespective of the amount of carbon dioxide liquid in the container. The only wholly satisfactory method of ascertaining the amount of carbon dioxide is by Weighing the container,

a method which is not practical in small installations such as automatic coin operated dispensing units for carbonated beverages. Difliculty has been had with such units because the carbon dioxide supply in one container becomes depleted resulting in the failure of the unit to carbonate the beverage and necessitating additional servicing of the unit to change to a full container. In other instances, the container of carbon dioxide is replaced long before it is necessary to do so, thus resulting in waste.

The present invention aims to overcome the foregoing difiiculties by providing a changeover valve adapted to be connected between the two containers and. the piping system of a carbonator or other device, the valve automatically closing off the used container when the container pressure drops below a predetermined amount and simultaneously opening the reserve container to the piping system.

In accordance with the invention this is accomplished by providing the system with a changeover valve which includes a housing for a pair of interconnected valve members, each valve member being adapted to close off a fluid passage leading to its source of supply. The two supplies are respectively termed the first source and the reserve source. It is immaterial as to whether or not the source of greatest pressure is first connected to the changeover valve as the changeover valve will automatically assume a position so that the source first connected will first supply the system irrespective of its starting pressure as long as its starting pressure is over a predetermined changeover valve. In the changeover valve, fluid pressure against a valve member from the first source connected to the changeover valve is adapted to unseat the valve member and move the reserve source valve member into its closed position. The connecting means between the first source and the reserve valve members includes resilient means and a pressure seated valve member adapted to close an opening to the atmos phere. The effective area of the pressure seated valve member is predetermined so that the reserve valve member is held closed against the pressure of its source by a predetermined pressure above atmosphere tending to seat the pressure seated valve member. The first source valve member remains open until the pressure of its source has dropped to the predetermined pressure over atmosphere.

After the pressure of the first source has dropped to the predetermined valve, the force exerted by the resilient member moves the pressure seated valve member oii from its seat which not only practically eliminates the pressure effect holding the reserve source valve member closed but also relieves the compression on the resilient member holding the reserve valve member on its seat, thus, assuring a quick and positive changeover. Fluid from the reserve source is then released and causes duplicate mechanism connected therewith to compress a resilient member to urge the valve member of the first source onto its seat.

A valve in accordance with the invention is advantageous in that it is actuated by the pressure of the fluids from one or the other of the supply sources and requires no outside connection of any sort. The construction of the changeover valve is such that either source may be used first, the valve automatically selecting as a supply the first source from which pressure is applied to the valve.

Other objects and advantages of the invention will be apparent from the following description and from the accompanying drawings in which is 3 shown, by way of example, an embodiment of the invention.

In the drawings:

Fig. 1 is a side view of a system utilizing a changeover valve in accordance with the invention.

Fig. 2 is a side view of the changeover valve.

Fig. 3 is a central vertical sectional view of the changeover valve.

Fig. 4 is a bottom view of the changeover valve.

Fig. 5 is a longitudinal vertical sectional view of the changeover valve in a neutral position.

Fig. 6 is a longitudinal vertical section of the changeover valve in a position opening a source to the left to the piping system and closing a source to the right therefrom.

Fig. '7 is a longitudinal vertical section of the changeover valve in a position opening a source to the right to the piping system and closing a source to the left therefrom.

Referring to the drawings, there is shown in Fig. l a system in accordance with the invention. The system comprises a container 2 for a fluid medium, connecting piping 3 leading to a changeover valve 4, a reserve container 5, connecting piping 8 leading from the reserve container 5 to the changeover valve 4, and a delivery pipe I leading from the outlet of the changeover valve 4 to any device such as a carbonator (not shown) in which both normal and reserve supplies of fluid are used.

The containers 2 and 5 may be of the usual type to store a fluid medium under pressure. Each container is fitted with a closure member or valve 9 to releasably retain the fluid in the containers. Upon connecting the containers to the changeover valve 4 the closure members 9 may be opened, the changeover valve 4 thereafter retaining the fluid in the respective containers and releasing it as required.

The changeover valve 4 comprises a housing I which in the form shown has inlets H and !2 at opposite ends thereof while the outlet [4 is posi tioned at the top of the housing. Both inlet ends of the housing Iii are similarly constructed and include hollow portions which provide cylinders i for the reciprocation of pressure seated valve members l5. Each cylinder is closed at its outer end by a plug member I! having a fluid passage is extending therethrough, the outer end of the fluid passage being enlarged and threaded to receive a pipe connector 20. The fluid passage l9 at the inner end of the plug member I! is enlarged to form a valve chamber for an inlet valve member 2|, a valve seat 22 being formed about the fluid passage is. The plug member is sealed in the housing it) by an O-ring gasket 23 positioned in a gasket recess 24 in its wall. The inlet valve member 2| is preferably provided with a seating surface 25 of corprene, nylon or other material adapted to provide a fluid-tight seal and its side wall 28 is formed of polygonal section to guide the valve member in its chamber and to permit the passage of the fluid medium between the side wall of the valve member and the wall of the chamber. An extension 21 of the valve member 2i is adapted to be received within the end of a resilient member or spring 29.

The pressure seated valve member i6 is loosely fitted within the cylinder IS, the side wall of the pressure seated valve member having a poly gonal sectional shape to permit the leakage of a certain amount of fluid to pass the pressure seated valve as will hereafter appear. A rod or extension 30 of the pressure seated valve member I6 is loosely fitted in and passes through an apertured wall 3! forming the bottom of cylinder i5, the loose fit providing venting fluid passage means from the chamber to the atmosphere. A valve seat 32 is positioned about the aperture for the rod. The bottom of the pressure seated valve member :6 is provided with a seating surface 33 of corprene, nylon or other suitable material, so that the pressure seated valve member is adapted to engage with the valve seat 32 to seal the cylinder against fluid leakage through the apertured wall 3i when the pressure seated valve is at the inner end of the cylinder.

The relative values of the efiective area of the pressure seated valve member is and of its valve seat 32 as compared to the area of the opposite inlet valve seat are important in the proper operation of the changeover valve 4, and must be such that the opposite inlet valve member will be held on its seat against the high pressure of the fully charged reserve container and remain closed until the pressure of the first container has dropped to a predetermined value.

The resilient member or spring 29 preferably should have suflici nt recoil or elasticity so that it will hold its reserve container inlet valve against its seat even though the pressure seated valve member has moved slightly away from its seat.

Fluid passage means 33 are provided in the housing leading from each of the cylinders I5 and manifolded to the outlet M. The fluid passages are each provided with check valves 34 to restrict the flow of fluid from the outlet I4 to the cylinder !5 while allowing the flow of fluid from the inlets i i and I 2 to the outlet l 4. In each of the fluid passages 33 an enlarged portion 35 is formed to provide a valve chamber for the check. valve $4, a valve seat 36 being formed at the entrance to each of the valve chambers about the fluid passage 33. The valve members 34 are provided with seating surfaces 31 the valve members being held against the seats 36 by resilient members or springs 39 adapted to engage between the valve members and the under sides of check valve caps 40 threadedly engaged in the housing [0. The outlet end of the fluid passage 33 is enlarged and threaded to receive an outlet pipe connector 4 I.

Provision is made for indicating the pressure of the fluids in each of the containers by permanently mounting gauges on the changeover valve 4. Each of the plug members I! is provided with a passage 42 leading from the fluid passage Hi to an annular recess or groove 44 formed on the outer wall of the plug member. Both inlet ends of the housing It] are formed with a fluid passage 45 connecting with the groove 44 and enlarged and threaded at its outer end to receive a connection fitting 46 of a gauge 41. Thus each of the gauges 47 is adapted to indicate the pressure of its source irrespectively of the position of the inlet valve members 2l. As may be seen in Fig. 3, the outlet !4 may be oifset somewhat to allow greater clearance in tightening the gauge connections 46.

Indicating means are provided to show the positions of the pressure seated valve members [5 which, as will be hereafter explained, control the opened and closed positions of the inlet valve members 2 I. Each of the rods 36 are formed with recesses 49 at their outer extremities adapted to receive the ends of a pin 56 which is adapted to secure the perforated end of a flat member 5| having outwardly turned ends 52 carrying a plate 5. 54. -As the pressure seated valve members are reciprocated from side to side of the valve the flat member is moved in the space 53 between the walls 3| forming the ends of the cylinders [5. A frame 55, having an opening 56 therein, is attached to the housing of the plate 54 by screws 51 or other suitable attaching means. A doubleended arrow is stamped or painted on the plate 54, the arrow being of a size and positioned so that only one of its ends is visible at a time through the opening 56 of the frame 55 depending on the position of the pressure seated valve members and thus indicating which one of the sources of fluid medium are connected to the outlet.

In operating the system in accordance with the invention, the containers of fluid medium are connected to the changeover valve and to the piping system in the usual manner. Before pressure is applied to the changeover valve 4 its parts assume the positions shown in Fig. 5. It will be noted that the pressure seated valve members 16 assume a position midway between the opened and closed positions so that both of the inlet valve members are unseated as shown in Fig. 5. One of the valves 9 may be opened allowing the fluid from that container to flow to the changeover valve. The construction of the changeover valve is such that the first container from which pressure is applied to the valve positions it so as to close off the flow of fluid from the other container until the pressure of the first container has dropped to a predetermined amount, at which time the check valve of the second or reserve cylinder is opened to the outlet. As may be seen in Fig. 6, the fluid entering the changeover valve 4 through its inlet H passes the unseated check valve 2| and causes the pressure seated valve member [6 to move to the end of the cylinder 15. The fluid also unseats the check valve 34 and passes through the outlet IA. The movement of the pressure seated valve member [6 and its rod 30 outwardly also moves the pressure seated valve member of the reserve supply and compresses the reserve supply spring 29 to urge the reserve container check valve 2| against its seat 22. With this position of the mechanism of the changeover valve, the reserve container valve 9 may be opened to make the reserve container fluid available for use after the fluid medium has been exhausted from the first container. By reason of the construction in which the pressure seated valve member for each supply is made with an area larger than the area of the valve seat of the inlet of the other supply, a small amount of pressure of fluid from one source on its pressure seated valve member will hold the inlet valve member for the other supply against its seat through the compression of its spring 29. Each of the springs 29 are designed with a compression strength so that upon the dropping of the pressure in the first container to a predetermined amount its pressure seated valve member is urged away from its position at the end of the cylinder by the stored energy of the opposite spring 29 for the other or reserve container. The movement of the pressure seated valve simultaneously relieves the pressure with which the spring member holds the reserve container inlet valve against its seat and upon the dropping of the pressure of the first container to a predetermined amount the pressure of the fluid in the reserve container will unseat the reserve container inlet valve member, thus allowing fluid from the reserve container to flow into the reserve container valve cylinder and act on the reserve container pressure seated valve member to cause it to close off the inlet valve 6. member for the first container; The changeover valve is then positioned for the reserve container fluid to flow through the outlet M. By reason of the loose fit of the pressure seated valve member IS in its cylinder i5, as soon as it moves away from it valve seat 32 the fluid will leak past it and through the rod aperture to the atmosphere to assure a rapid action of the changeover from the normal to the reserve container. The positions of the parts of the changeover valve when discharging the reserve container 5 are shown in Fig. 7. The movement of the rods 30 causes the indicator plate 54 to be shifted from one side to the other uncovering the end of the arrow pointing towards the reserve container now being used, thus a visual indication is given of the container connected to the outlet. The gauges t! indicate the pressure of the fluid medium of the reserve containers. The discharged container 2 may then be disconnected and replaced with a charged container without interruption of the discharge from the reserve container 5.

It is thus apparent that a fluid system and a changeover valve therefor have been provided in accordance with the invention in which a reserve supply of fluid medium is automatically put into service upon the dropping of the pressure of the first source of supply below a predetermined value.

While the invention has been described and illustrated with reference to a specific embodiment thereof, it will be understood that other embodiments may be resorted to without departing from the invention. For example, while a changeover valve has been described with its pressure seated valve members in axial alignment, it is obvious that a construction might be utilized in which the pressure seated valve members are placed side by side, using a rocker arm or other similar construction for connection therebetween. Therefore, the form of the invention set out above should be considered as illustrative and not as limiting the scope of the following claims.

I claim:

1. A changeover valve comprising a housing, means providing a pair of inlets and an outlet for the housing, means in the housing for closing one inlet from the outlet, pressure holding means to releasably maintain the closing means in the closed position, means to lead fluid from the open inlet to one side of the pressure holding means, and means leading from the housing to vent the other side of the pressure holding means.

2. A changeover valve comprising a housing, means providing a pair of inlets and an outlet for the housing, means in the housing for closing one inlet from the outlet, pressure holding means to releasably maintain the closing means in the closed position, means to lead fluid from the open inlet to one side of the pressure holding means, means leading from the housin to vent the other side of the pressure holding means, and resilient means interposed between the pressure holding means and the closing means.

3. A changeover valve comprising a housing, means providing a pair of inlets and an outlet for the housing, a valve in the housing for closing one inlet from the outlet, means providing a vent from the housing, a seat about the vent, and a pressure holding member to engage the seat responsive to the pressure of fluid from the open inlet and adapted to releasably hold the valve member in the closed position.

4. A changeover valve comprising a housing, means providing a pair of inlets and an outlet for the housing, a valve in the housing for closing one inlet from the outlet, means providing a vent from the housing, a seat about the vent, a pressure holding member to engage the seat responsive to the pressure of fluid from the open inlet and adapted to releasably hold the valve member in the closed position, and a spring interposed between the valve and the pressure holding member.

5. A changeover valve comprising a housing having a pair of inlets and an outlet, a valve to close each inlet, means providing a pair of vents from the housing, a seat about each vent, a pressure holding member to engage each seat and responsive to the pressure of fluid from the adjacent inlet and adapted to hold the other valve member in the closed position, and a connecting member for the pressure holding members to move one into the holding position as the other is moved away from the holding position.

6. A changeover valve comprising a housing having a pair of inlets and an outlet, a valve to close each inlet, means providing a pair of vents from the housing, a seat about each vent, a pres sure holding member to engage each seat and responsive to the pressure of fluid from the adjacent inlet and adapted to hold the other valve member in the closed position, a connecting member for the pressure holding members to move one into the holding position as the other is moved away from the holding position, and a spring interposed between each pressure holding member and the other valve member so that the valve member is resiliently held in the closed position against its incoming pressure.

7. A changeover valve comprising a housing having a pair of inlets and an outlet, a valve to close each inlet, means providing a pair of vents from the housing, a seat about each vent, a pres sure holding member to engage each seat and responsive to the pressure of fiuid from the adjacent inlet and adapted to hold the other valve member in the closed position, a connecting member for the pressure holding members to move one into the holding position as the other is moved away from the holding position, a backfiow check valve interposed between each inlet valve and the outlet, and a spring interposed between each pressure holding member and the other valve member so that the valve member is resiliently held in the closed position against its incoming pressure.

8. A changeover valve comprising a housing having a pair of inlets and an outlet, a valve seat about each inlet, a valve member for each inlet adapted to be seated against the incoming pressure, means providing a valve chamber about each inlet valve, vent means for each valve chamber, a seat about each vent, a pressure holding member in each valve chamber and adapted to engage the vent seat to close the vent, a connecting member between the pressure holding mem bers to reciprocate one into the vent seat engaging position as the other is moved away from its seat engaging position, and check valve means interposed between each valve chamber and the outlet.

9. A changeover valve comprising a housing having a pair of inlets and an outlet, a valve seat about each inlet, a valve member for each inlet adapted to be seated against the incoming pressure, means providing a valve chamber about each inlet valve, vent means for each valve chamber, a seat about each vent, a pressure holding member in each valve chamber and adapted to engage the vent seat to close the vent, a connecting member between the pressure holding members to reciprocate one into the vent seat engaging position as the other is moved away from its seat engaging position, check valve means interposed between each valve chamber and the outlet, and a spring interposed between each connecting member and the valve member in its valve chamber.

10. A changeover valve comprising a housing having a pair of opposed inlets and an outlet, a valve seat within the housing about each inlet, means providing a valve chamber about each inlet, an inlet valve member for each inlet adapted to engage its seat against the incoming pressure, means providing aligned guideway openings in the walls of the valve chambers, a connecting member adapted to be reciprocated in the guideways, a pressure holding member in each valve chamber and attached to the connecting member, vent means for each valve chamber, a seat in the valve chamber for each vent, the pressure holding member adapted to engage the vent seat to close the vent, a spring interposed between the pressure holding member and the inlet valve member in each valve chamber, check valve means interposed between each valve chamber and the outlet to prevent backflow from the outlet to the valve chamber.

NORMAN HARRY SIEBENS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,138,988 Thomas Dec. 6, 1938 2,138,989 Thomas Dec. 6, 1938 2,247,520 Paxton July 1, 1941 2,311,851 McClure Feb. 23, 1943 2,389,667 Hudson Nov. 27, 1945 2,400,108 Elowson May 14, 1946 2,401,258 Livers May 28, 1946 FOREIGN PATENTS Number Country Date 39,579 Sweden of 1915 

